This is LaTeX code:
[latex]
[(a_1,a_2,a_3)o(b_1,b_2,b_3)]o(c_1,c_2,c_3)=(c_1(a_1b_1),c_2(a_2b_1+b_2),c_3(a_3b_1+b_3))
[/latex]